GENETICS, BIOMARKERS, AND NEUROPATHOLOGY (GBN) CORE: ABSTRACT The goal of the GBN Core is to support the efforts of PANUC to understand and treat cognitive impairment (CI) in Parkinson's disease (PD) and models of PD through human and animal studies. GBN provides logistical and analytical support to all four Projects and the Clinical Resource Core of PANUC as well as to linked U01 NS082137, one of ten projects funded by the NIH Parkinson's Disease Biomarker Program (PI: Dr. Zhang, also co-Leader of GBN Core). We will accomplish our goal through the following Specific Aims: Specific Aim 1. GENETICS: Genotype new Clinical Resource Core participants for entry into Project 3 and Project 4, and validate putative genetic risk factors for CI in the PD Cognitive Genetics Consortium. Specific Aim 2. CSF BIOMARKERS: Provide analysis of well established biomarkers for PD and Alzheimer's disease using CSF assays routinely performed in the GBN Core. Specific Aim 3. NEUROPATHOLOGY: Provide expert analysis of tissue samples from Projects and Cores. Specific Aim 4. DATA MANAGEMENT and STATISTICS: Provide expert data management and statistical support for the Clinical Resource Core and all Projects and analyze the high dimensional data collected in this Core. The GBN Core serves several initiatives in the NIH Blueprint. It uses existing NIH resources, contributes essential materials to NIH repositories, and is highly patient- oriented and translational.